1. Field of the Invention
This invention relates to apparatus for displaying characters on a display unit of a television receiver and more particularly for apparatus for displaying a number designating a channel to which the receiver is tuned.
2. Description of Prior Art
It is known in the prior art to display a channel number indicating the frequency to which a television receiver is tuned on the mechanical switch providing course tuning of the television receiver or by having the mechanical switch controls separate display apparatus. The switch determining the channel to which the television receiver is currently tuned and the display, controlled by the switch position, automatically displays the channel number. More recently, apparatus has been provided to tune the television receiver electronically in order to eliminate the problems associated with mechanical apparatus. A portion of the electronic apparatus can be used to drive the external display apparatus. It would be more convenient to incorporate, to the extent possible, the display of the television channel in the electronic tuning apparatus.
It is also convenient to display the current channel on the television screen concurrently with tuning to that channel, or upon a request signalled to the receiver for identification of the channel to which the television receiver is currently tuned. Such an arrangement eliminates the need for a separate external display device. Furthermore, the display of the channel, whether upon tuning or upon interrogation of the receiver tuning, must be made temporary in order not to interfere with received channel information.
It is therefore an object of the present invention to provide an improved character generator for use with a television receiver display unit.
It is another object of the present invention to provide a television receiver character generator for use with a display unit having a plurality of segments.
It is a still further object of the present invention to provide a display of alpha/numeric characters on a television display unit having size control mechanism.
It is yet another object of the present invention to provide a character generator for use with a television display unit having size-controllable characters and a cursive slant.
It is a more particular object of the present invention to provide a character display apparatus for use with a television receiver display unit having horizontal and vertical clocking apparatus for determining the position of component segment of the displayed characters.
It is still a further object of the present invention to provide a mechanism for controlling the size of characters displayed on a television receiver in response to input signals.
It is yet still a further object of the present invention to provide characters which disappear from the display unit by continuously decreasing in size.